Getting Ready to Fly

After installing the required tools, please follow the below described steps to prepare for your first flight.

1.Raspberry Pi Bootup

Connect the battery to powerup Raspberry Pi.

Once the Raspberry Pi is connected to the internet, you should see its IP address on the LCD screen.

The onboard computer(Raspberry Pi) has the necessary script already running at boot. Any errors with the Otus Quadcopter will be displayed on the LCD screen.

2. RCBenchmark Tracking Lab

Launch the RCbenchmark Tracking Lab.

Check if the Otus is being tracked. This can be done by checking if you have a visual tracking of the Otus Tracker on the RCbenchmark Tracking Lab GUI.

Once you have tracking of the Otus Quadcopter, place the Quadcopter in the center of the test area. Reset the axis by clicking the Reset local axis button on the SERVER tab of the Tracking Lab.

(Optional) To enable recording, enter the save file directory details on the TRACK tab of the RCBenchmark Tracking Lab.

Click on SERVER tab and enter the IP address of the Otus Quadcopter. Ensure that the port number is set to 5401. (as shown in the image above). If you are using multiple drones, the last three digit of the drone IP should be replaced by 255. For example, 192.168.2.255. The 255 address is the broadcast address, meaning that all computer on the network will receive the data packet containing the position information.

Toggle Streaming ON to enable motion capture using the Otus Tracker.

Your quadcopter is now enabled with motion capture.

3. Flying with Multiple Quadcopters (Optional)

We recommend to complete this part once you have completed the setup with a single quadcopter. When we ship an Otus Tracker with a quadcopter, this section should already be completed. but you may need to revisit it if you swap two Otus Trackers, or if you ordered the quadcopter and the Otus separately.

The Otus Tracker system can be used with multiple drones. Each Otus Tracker has an unique ID. This ID can be found underneath the Otus tracker. It is also available in the RCbenchmark tracking lab under Tools in the tab Track.

When using multiple trackers, each drone needs to know which tracker it is lined with. This is done by setting the flag --controller_id in the launch command of the RCB_pose_forward.py script. Note that if no flag is set, the quadcopter will receive the position of all connected trackers. Thus, if no flag is set and multiple trackers are connected, there will be a conflict and the drone will not fly.

If you wish to control each quadcopter separately you need to set the flag --controller_id. Once the value is set and the script is relauched, the ID will be shown on the LCD screen of the Otus quadcopter indicating that the quadcopter forwards the motion capture information only from the particular ID it is setup with.

4. QGroundControl

Launch QGroundControl on your main computer, this will automatically connect to the Otus Quadcopter. In case the connection is not automatic, navigate to Settings by clicking on the Q icon then click on Comm Links.a. Enter your choice of name as the name of the network. Here, we have chosen to go with the name, UDP 2.
b. Enter the listening port as 14551. c. Now, we can enter the IP address of the quadcopter coupled with the port number.

The IP address of the quadcopter can be found on the LCD display. Enter the IP address in the order as shown in
in the image.

d. Click on OK. Now your connection information is saved and a connection has been established with the quadcopter.

Once the quadcopter has been connected, you should see the result as shown below with the header displaying Manual and Disarmed with PX4 pro's logo on the extreme right of the header.

Once the Quadcopter is connected, click on Widgets and then click on Analyze as shown in the image below.

The scripts running on the Otus Quadcopter constantly communicate with the QGroundControl conveying the position (from the Pixhawk) and the vision estimate (from the Otus Tracker).In order to verify this on the Analyze window, find the following parameters: LOCAL_POSITION_NED.x andVISION_POSITION_ESTIMATE.x by typing the same on the search bar below (indicated in the image where "rcbenchmark" is written).Move the quadcopter along the X-axis (co-ordinate directions are engraved on the Otus Tracker). You should see the local and the vision position estimates overlapping and tracking the position of the quadcopter.Note: The readings are in centimeters and the slight errors you see are in millimeters.

Similarly, search for the parameters, ATTITUDE.yaw and VISION_POSITION_ESTIMATE.yaw in the search bar. Rotate the quadcopter along the Z-axis and verify that the local and the vision estimates are tracked together without any errors as displayed in the image below.Note: The readings are in centimeters and the slight errors you see are in millimeters.

The quadcopter is now tracking its position coordinates in real time using the Otus Tracker for motion capture. If you wish to monitor the scripts running on the on-board Raspberry Pi, you could follow the next step. Otherwise, you can navigate to the next page for Pre-flight checks and first flight.

5. SSH to the Raspberry Pi through PuTTY (Optional)

To monitor the scripts running on the onboard computer, you can SSH to the Raspberry Pi through PuTTY.

Launch PuTTY and enter the IP address of the quadcopter (displayed on the LCD screen). Then, click Open.

You will prompted to enter a password. By default Raspberry Pi's password is pi. Enter the password.

Notice that you are now logged in and you should a similar screen as shown below:

Enter the following command

screen -r

since there are multiple screens running, you will be shown a similar image as depicted below:

Enter the following command with the screen number to attach to that specific screen."-x" command attaches and resumes the detached screen.

screen -xr screen_number

Now, you are attached to that specific screen and you can monitor the running scripts.

If you want to terminate the script manually, press Ctl + Enter.

If you are using a Mac as an main computer, you do not need to installl PuTTY, you can directly ssh to the Raspberry Pi from the terminal using the following command. Where the IP_Address is the IP address of the Raspberry Pi.

Note: Please note that RCbenchmark Tracking Lab is not available for MacOS yet which means that the Otus Tracker cannot be used with Mac as a main computer.. ( This step is written assuming that you have used a different motion capture solution)

ssh pi@IP_Address

Please read through the Your Frist Flight & Safety section next for a run down of the first flight checklist and general safety instructions.